Compressor with Z-plate

ABSTRACT

A compressor is provided which minimizes impact noise and abrasion between a Z-plate of the compressor and vanes formed in the compressor. Ends of the vanes formed in the compressor contact sides of the Z-plate, and the motion and surface configuration of the Z-plate cause the vanes to move reciprocally and to section compression spaces within the compressor into a suction area and a compression area. Due to the curvature of the surfaces of the Z-plate, the vanes remain in constant contact with the surface of the Z-plate, which allows for smooth transition phases and a subsequent reduction in impact noise and abrasion between the vanes and the Z-plate.

TECHNICAL FIELD

The present invention relates to a compressor with a Z-plate, a kind ofrotary compressor, and, more particularly, to a compressor with aZ-plate in which a plane portion provided at both top dead centers of aZ-plate meet other curved portion with a curved line.

BACKGROUND ART

In general, a compressor is a device for converting a mechanical energyinto a compression energy of a fluid. And, depending on a compressionmethod, a freezing compressor is classified into a reciprocatingcompressor, a scroll compressor, a centrifugal compressor and a rotarycompressor.

The applicant of the present invention has filed an application for adevelopment of a compressor with Z-plate with a novel conception, thatcan be classified as a rotary compressor, which was laid open on May 7,2001 with a Korean Patent Publication No. 2001-0035687.

The compressor with a Z-plate in accordance with a conventional art willnow be described with reference to FIG. 1.

The conventional compressor with a Z-plate includes an electricmechanism unit consisting of a stator (Ms) and a rotor (Mr) whichgenerate a driving force at an upper portion inside a casing 1 and acompression mechanism unit connected to the rotor (Mr) and sucking,compressing and discharging a fluid.

The compression mechanism unit includes a cylinder 2 fixed at a lowerportion of the casing 1, first and second bearing plates 3A and 3B fixedat an upper face and a lower face of the cylinder 2 and forming an innerspace of the cylinder 2, a rotational shaft 4 coupled at the rotor (Mr)of the electric mechanism unit and penetratingly coupled at the bearingplates 3A and 3B to transfer a driving force of the electric mechanismunit to the compression mechanism unit, a Z-plate 5 coupled at therotational shaft 4 or integrally molded to section the inner space ofthe cylinder 2 into first space (S1) and second space (S2), first andsecond vanes 6A and 6B of which a lower end and an upper end isrespectively in contact with both faces of the Z-plate 5 so as tosection each space S1 and S2 into a suction area and a compression areawhen the rotational shaft 4 is rotated, and first and second springassemblies 8A and 8B for elastically supporting the vanes 6A and 6B.

With reference to FIG. 2, the Z-plate 5 is formed as a disk type in viewof a plane projection so that its outer circumferential face canslidably contact an inner circumferential face of the cylinder 2. Whenunfolded, the side of the Z-plate 5 forms a curved portion 5 a in a sinewave shape.

Both top dead center portions of the Z-plate 5 are in contact with eachbearing face of the first bearing plate 3A and the second bearing plate3B, and the contact portion forms a plane portion 5 b so as to enlarge asealing area by being in surface-contact with the bearing faces of eachof the bearing plates 3A and 3B.

The first vane 6A and the second vane 6B are formed as a rectangularparallelepiped, of which each upper end is supported by the springassemblies 8A and 8B and each lower end penetrates each of the bearingplates 3A and 3B so as to be in contact with both upper and lower sidesof the Z-plate 5.

In FIG. 1, reference numerals 2 a and 2 b are suction passage of eachspace, 3 a and 3 b are discharge passages, 7A and 7B are dischargemufflers, 7 a and 7 b are discharge holes, DP is a discharge pipe, andSP is a suction pipe.

The compressor with the Z-plate in accordance with the conventional artis operated as follows.

When the rotor (Mr) is rotated as power is applied to the electricmechanism unit, the rotational shaft 4 coupled at the rotor (Mr) isrotated in one direction together with the Z-plate 5, and the vanes 6Aand 6B being in contact with both upper and lower sides of the Z-plateare reciprocating in the opposite direction, varying a capacity of thefirst space S1 and the second space S2. In line with this, a fresh fluidis simultaneously sucked through each of suction passages 2 a and 2 b ofthe first space S1 and the second space S2, gradually compressed andthen discharged through the discharge passages 3 a and 3 b of the spacesS1 and S2 at the instant when the upper dead center or the lower deadcenter of the Z-plate 5 reaches the discharge initiation point.

However, in the compressor with the Z-plate in accordance with theconventional art, the portion (θ1, θ2) where the curved portion 5 a andthe plane portion 5 b of the Z-plate 5 meet each other is formed with anedge, so that when the vanes 6A and 6B behave, a minute liftingphenomenon occurs, causing a fluid leakage and an impact noise.

In addition, as the edge portion where the curved portion 5 a and theplane portion 5 b meet contacts the contact surface of the vanes 6A and6B or contacts the bearing surface of the bearing plates 3A and 3B, anabrasion occurs due to scratch, and in worst case, a crack is generatedbetween both spaces centering around the plane portion 5 b, which wouldcause a compressed fluid leakage. This would result in a degradation ofa compression performance.

DISCLOSURE OF THE INVENTION

Therefore, an object of the present invention is to provide a compressorwith a Z-plate that is capable of preventing abrasion of a vane or abearing plate as well as a fluid leakage or an impact noise bystabilizing a behavior of the vane being in contact with a Z-plate,thereby promoting improvement of performance of a compressor.

To achieve these and other advantages and in accordance with the purposeof the present invention, as embodied and broadly described herein,there is provided a compressor with a Z-plate having a cylinder with asuction passage and a discharge passage, a Z-plate sectioning an innerspace of the cylinder into a plurality of compression spaces and beingrotated by a driving unit so that a fluid can be sucked, compressed anddischarged, and vanes moved reciprocally by being in contact with bothsides of the Z-plate to thereby suction the compression space into asuction area and a compression area, wherein the Z-plate includes acurved portion formed with a particular function for the both sidesbeing in contact with the vane, a plane portion formed around aninflection point of the curved portion including the inflection point,and a gentle portion formed round between the curved portion and theplane portion.

The foregoing and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

In the drawings:

FIG. 1 is a vertical-sectional view showing an example of a compressionwith a Z-plate in accordance with a conventional art;

FIG. 2 is a perspective view showing a Z-plate of the compressor of FIG.1 and a sectional view of a major part;

FIG. 3 is a graph showing a development of a cam surface of the Z-plateof the compressor in accordance with the conventional art;

FIG. 4 is a perspective view of a Z-plate of a compressor with a Z-platein accordance with the present invention;

FIG. 5 is a graph showing a development of a cam surface of the Z-plateof the compressor in accordance with the present invention; and

FIG. 6 is a graph showing that the cam surface of the Z-plate can bechanged with diverse functions for implementation in the compressor witha Z-plate in accordance with the present invention.

MODES FOR CARRYING OUT THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings.

FIG. 4 is a perspective view of a Z-plate of a compressor with a Z-platein accordance with the present invention, and FIG. 5 is a graph showinga development of a cam surface of the Z-plate of the compressor inaccordance with the present invention.

With reference to FIG. 1, a compressor with a Z-plate in accordance withthe present invention includes: a cylinder 2 coupled at one side of anelectric mechanism unit and fixed at a casing 1, first bearing plate 3Aand second bearing plate 3B fixed at the an upper surface and a lowersurface of the cylinder 2 and forming an inner space of the cylinder 2together; a rotational shaft 4 coupled at the electric mechanism unitand penetratingly coupled to the bearing plates 3A and 3B so as totransfer a driving force of the electric mechanism unit to a compressionmechanism unit; a Z-plate 10 (refer to FIG. 4) coupled at or integrallymolded with the rotational shaft 4 and sectioning the inner space of thecylinder 2 into a first space S1 and a second space S2; and first andsecond vanes 6A and 6B being in contact in its lower end and its upperend with both sides of the Z-plate 10 and sectioning the spaces S1 andS2 into a suction area and a compression area when the rotational shaft4 is rotated.

The compressor of the present invention has the same construction asthat of the conventional compressor, except for the Z-plate 10 as shownin FIG. 4.

The Z-plate 10 is formed as a disk type in view of plane projection sothat its outer circumferential face can slidably contact an innercircumferential face of the cylinder 2.

In addition, as shown in FIGS. 4 and 5, both sides of the Z-plate 10 areformed as a cam surface in a sine wave shape. Each cam surface includesa curved portion 11 implemented by a particular function from the lowerdead point to certain intervals (0˜θ₁) (θ₄˜2π) of the both sides, agentle portion 12 formed round from the curved portion 11 to a certainintervals (θ₁˜θ₂) (θ₃˜θ₄) of the both sides, and a plane portion 13including an inflection point at the certain interval (θ₂˜θ₃) betweenboth ends of the gentle portion 12.

With reference to FIG. 1, as for the first vane 6A and the second vane6B formed as rectangular parallelepiped, its upper end is supported byspring assemblies 8A and 8B, and its lower end penetrates the bearingplates 3A and 3B and coupled to be in contact with the both upper andlower sides of the Z-plate 10.

For reference, the same reference numerals are given to the sameelements as those in the conventional art.

The operation and effect of the compressor with the Z-plate of thepresent invention will now be described.

When power is applied to the electric mechanism unit, the rotationalshaft 4 is rotated in one direction together with the Z-plate 10,according to which each capacity of the first space S1 and the secondspace S2 is varied and a fresh fluid is simultaneously sucked into eachspace, compressed and then discharged.

At this time, the vanes 6A and 6B being in contact with upper and lowersides of the Z-plate 10 are moved reciprocally in the opposite directionalong the high and low of the Z-plate. In this respect, since the bothcam surfaces of the Z-plate 10 includes the gentle portion 12 roundlyconnecting the curved portion 11 and the plane portion 13, as well asthe curved portion 11 and the plane portion 13, the vanes 6A and 6B canslidably moved while maintaining the state of being in constantlycontact with the cam surfaces of the Z-plate 10.

Therefore, an impact noise between the vanes 6A and 6B and the Z-plate10 caused when the vanes 6A and 6B are abruptly detached from theZ-plate 10 and then attached back can be prevented. And since theconnecting portion between the curved portion 11 and the plane portion13 of the Z-plate 10 is formed round, the bearing faces of the bearingplates 3A and 3B where the Z-plate 10 slidably contacts can be preventedfrom being abraded by being scratched by the Z-plate.

Meanwhile, as shown in FIG. 6, the curved portion 11 and the gentleportion 12 can be successively combined by differentiating the functionin every certain interval (0˜θ₁)(θ₁˜θ₂), . . . , (θ₁₂˜θ₁₃) (θ₁₃˜2π).

That is, provided that the sine wave curved line corresponds to thecurved line of ‘I’ in FIG. 6, the value of the function forming thecurved surface can be set larger or smaller so as to becomes the curvedline of ‘II’ or the curved line of ‘III’.

At this time, the vanes 6A and 6B respectively being in contact withboth upper and lower sides of the Z-plate 10 are moved reciprocally inthe opposite direction along the high and low of the Z-plate 10. Thus,in case that both cam surfaces of the Z-plate 10 are formed such thatevery interval is formed to be curved symmetrically with combinations ofdifferent functions, a discharge initiation angle and compressionprocess can be variably changed to be designed and a discharge pulsationnoise can be reduced.

As so far described, the compressor with a Z-plate of the presentinvention has the following advantages.

That is, for example, since the region formed near the inflection pointamong the both sides being in contact with the vane, where the planeportion and the curved portion are connected to each other, is formedround, so that the vane is maintained in a state of constantlycontacting the cam surface of the Z-plate. Thus, an impact noise causedbetween the vane and the Z-plate can be prevented in advance andabrasion from scratch on the bearing face of the bearing plate can beprevented, so that a compression performance can be satisfactorilymaintained.

In addition, by forming the both cam surfaces of the Z-plate withcombinations of different functions for intervals, a dischargeinitiation angle and compression process can be designed to be variablychanged depending on a design conditions of a compressor in order toreduce a discharge pulsation and improve a compression performance.

As the present invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, itshould also be understood that the above-described embodiments are notlimited by any of the details of the foregoing description, unlessotherwise specified, but rather should be construed broadly within itsspirit and scope as defined in the appended claims, and therefore allchanges and modifications that fall within the meets and bounds of theclaims, or equivalence of such metes and bounds are therefore intendedto be embraced by the appended claims.

1. A compressor, comprising: a cylinder with a suction passage and adischarge passage; a Z-plate configured to section an inner space of thecylinder into a plurality of compression spaces and to be rotated by adriving unit so that a fluid can be sucked, compressed and discharged;and vanes configured to move reciprocally due to contact with both sidesof the Z-plate so as to section the compression space into a suctionarea and a compression area, wherein the Z-plate comprises a curvedportion formed based on a particular function such that both sides makecontact with a vane, a plane portion formed around an inflection pointof the curved portion and including the inflection point, and a roundedportion formed between the curved portion and the plane portion.
 2. Thecompressor of claim 1, wherein both sides of the Z-plate are configuredso as to maintain substantially constant contact with the respectivevanes.
 3. A compressor, comprising: a cylinder with a suction passageand a discharge passage; a Z-plate configured to section an inner spaceof the cylinder into a plurality of compression spaces and to rotate inresponse to a driving force generated by a driving unit so that a fluidcan be sucked, compressed and discharged; and vanes configured to movereciprocally based on contact with sides of the Z-plate so as to sectionthe compression space into a suction area and a compression area,wherein a shape of curved portions of the Z-plate which contact thevanes are formed based on combinations of multiple functions.
 4. Thecompressor of claim 3, wherein the Z-plate comprises: a curved portionformed based on multiple functions such that both sides make contactwith the respective vanes; a plane portion formed around an inflectionpoint of the curved portion and including the inflection point; and arounded portion formed between the curved portion and the plane portion.5. The compressor of claim 3, wherein the curved portions of the Z-platewhich contact the respective vanes are contoured so as to allow avariation of a discharge initiation angle.
 6. The compressor of claim 3,wherein both sides of the Z-plate are configured so as to maintainsubstantially constant contact with the respective vanes.
 7. Acompressor, comprising: a cylinder with a suction passage an a dischargepassage; a Z-plate configured to section an inner space of the cylinderinto a plurality of compression spaces and to rotate in response to adriving force generated by a driving unit so that a fluid can be sucked,compressed and discharged; and vanes configured to move reciprocallybased on contact with respective sides of the Z-plate so as to sectionthe compression space into a suction area and a compression area,wherein an upper dead center portion of the Z-plate is substantiallyplanar, and a portion of the Z-plate which does not form the upper deadcenter portion is formed as a curved surface which is connected to thesubstantially planar upper dead center portion by a rounded transitionportion.